The invention relates to soil working implements and, more particularly, relates to a soil working implement having a cultivator and one or more tine harrow sections articulated to the cultivator in a trailing relationship thereto. The invention additionally relates to a soil working implement of the above-mentioned type having a one point tine angle adjustment.
A wide variety of tillage implements are used to prepare soil for planting. Some such implements include two or more sections articulated to one another so as to perform multiple functions as they are pulled through fields by a single tractor or other prime mover. One such implement is a cultivator/harrow, which is capable of simultaneously tilling soil and leveling the tilled soil in preparation for planting. This implement includes a cultivator that is towed by a tractor or other prime mover, and a unitary or sectional tine harrow that is towed by the cultivator.
The cultivator includes a plurality of cultivator members or xe2x80x9csweepsxe2x80x9d (sometimes known as shanks or chisel plows) that are suspended from a frame and that rip into the soil as the machine is pulled across the ground to till the soil. The sweeps are arranged in transversely extending rows. The sweeps of each row are transversely staggered relative to the sweeps of the adjacent rows. In use, each successive row of sweeps tills part of a strip of soil left untilled by the preceding row. The last row of sweeps tills the last untilled strip of the swath, leaving ridges between the sweeps that are flanked by valleys directly behind the sweeps.
The harrow is designed to level the tilled soil sufficiently to produce a seedbed that is as level as possible and that is relatively clod free. A clod free, level seedbed formed from soil of relatively small particle size is desirable because it facilitates planting to a uniform depth and, accordingly, promotes uniform germination and uniform emergence. The typical harrow includes a plurality of grounded-engaging tines that penetrate the soil tilled by the cultivator. Multiple harrow sections are often provided, each of which spans a proportionate part of the transverse width of the swath tilled by cultivator. The tines are typically arranged in longitudinally extending, transversely spaced rows. They are intended to redirect soil from ridges or windrows left by the cultivator sweeps into the adjacent valleys, hence leveling the tilled surface. The tines, and/or related equipment such as rotating baskets, also firm the soil and break up clods.
Some harrows incorporate measures to permit rake angle adjustment. The xe2x80x9crake anglexe2x80x9d is the angle of inclination of the tine relative to ground. The rake angle of some harrows can be adjusted to adjust the force imposed on the ground by the tines in order to maintain a particular penetration-depth in different soil conditions or to set a new penetration depth for a particular soil condition.
However, tine rake angle adjustment typically requires the use of specialized tools and sometimes requires tine angle adjustment on a tine-by-tine basis. Considerable operator time and effort are required to make rank angle adjustments in these systems. Moreover, known mechanisms for adjusting rake angle do not assure that the rake angles of all tines will be altered uniformly. Undesirable variations of rake angle within a cultivator section often result.
The need therefore has arisen to provide a harrow having a rake angle that can be rapidly adjusted in the field without any specialized tools.
The need has also arisen to provide a rake angle adjuster for a harrow that assures that any rake angle adjustment imparts a uniform change in rake angle to all tines of a harrow section.
It is an object of the invention to avoid this disadvantages of the prior art by providing rake angle adjustment for a harrow that assures rake angle adjustment imparts a uniform change in the rake angle to all tines of a harrow section.
In accordance with the first embodiment of this invention, a tine harrow assembly including a frame member; plurality of tines pivotally connected to the frame member to permit a rake angle adjustment of the tines. The tines are arranged in a plurality of transversly extending rows. The adjustment mechanism is operably connected to the tines for effecting change in the rake angle. The adjustment mechanism includes a tine slide having a stop formed therein corresponding to each of the transverse row of tines. The tine slide being movable relative to the frame to position the stops at one of multiple selected positions. The transverse rows of tines being pivotable against the corresponding stops to define a selected rake angle. The cultivator section includes a plurality of transversely spaced cultivator members.
The tine slide may include a slide plate slidably mounted on a longitudinally-extending support member of the harrow assembly. The side plate is attached to the support member at any one of multiple mounting points along the support member. The number of mounting points equals the number of stop positions.
The side plate may include an access point for applying actuating forces to the side plate.
The access point may include a manually-accessible handle.
The stops may be formed integrally with the slide plate.
The tine harrow assembly may include a tensioner that is coupled to the tine slide and to support the frame member and that tensions the tine harrow assembly downwardly and forwardly.
The support may include a multiple tensioner attachment points corresponding in number to the number of stop positions. The tension is movable between the attachment points to maintain application of a generally constant tensioning force against the harrow assembly regardless of tine slide position.
The support may include a hitch of a harrow of which the tine harrow assembly is a part.
In accordance with a second embodiment of the invention, a method of adjusting a rake angle of a tine harrow assembly which includes a frame member and a plurality of tines pivotally connected to the frame member to permit a rake angle adjustment of the tines; the tines are arranged in a plurality of transversly extending rows, where the method includes the steps of moving a tine slide longitudinally of the frame member while simultaneously pivoting all of the rows of tines to maintain an abutting relationship between the rows of tines and a corresponding number of longitudinally spaced stops on the tine slide.
The method may further include the step of detaching the tine slide from the frame member prior to the moving step and reattaching the tine slide to the frame member after the moving step.
These and other features and advantages of the invention will become apparent to those skilled in the art from the following detailed description and accompanying drawings. It should be understood, however, that the detailed description and specific examples, while indicating preferred embodiments of the present invention, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the present invention without departing from the spirit thereof, and the invention includes all such modifications.